1. Field of the Invention
The present invention relates to an image forming apparatus that includes non-volatile storage means such as a hard disk drive and to a control method thereof, and relates more particularly to an image forming apparatus that minimizes the consumption of power during physical formatting of the hard disk drive or the deletion of data therefrom and to a control method thereof.
2. Description of the Prior Art
Many types of image forming apparatus that combine the various functions of a copier, fax machine, printer and the like have been commercialized in recent years. In such an image forming apparatus, several information terminal devices are connected over a network and large amounts of image information are input from these information terminal devices. In order to store these large amounts of input image information, the multifunction image forming apparatus must have a large-capacity storage device. Accordingly, the image forming apparatus has a non-volatile storage means such as a hard disk drive (hereinafter ‘HDD’) in addition to the volatile storage means used for image formation.
As such an HDD-equipped apparatus, an apparatus having an object of checking the consistency of the HDD management information when the power is turned ON in order to reduce the startup time has been disclosed (see, for example, Japanese Patent Application Laid-Open No. 2001-277603 or Japanese Patent Application Laid-Open No. 2001-285600). Specifically, in this apparatus, a temporary file storage area is made available when initialization thereof is completed, thereby enabling image processing functions to be performed. As a result, the amount of time required for the apparatus to reach operable status can be minimized.
In the conventional image forming apparatus, the storage capacity of the installed HDD is relatively small, such that initialization (physical formatting) of the HDD or deletion of all image data stored thereon (data clearing) can be carried out in a short period of time. Consequently, little concern has been given to the amount of power consumed during physical formatting or data clearing of the HDD included in the apparatus. However, increases in the number of functions handled by this type of apparatus and improvements in the processing capabilities thereof in recent years have required that the storage capacity of the HDD installed in the apparatus be increased accordingly, resulting in dramatic increases in such HDD capacity. As a result, the amount of time required for physical formatting and data clearing of the HDD has increased, thereby increasing the amount of power consumed during these operations.
An electrophotographic image forming apparatus in particular requires a heat fixing device to fix the toner onto the recording paper. A heat fixing device requires the consumption of a large amount of power even when it is on standby status. This is due to the fact that the heat rollers in the device must be continually maintained at a prescribed level in order to be able to carry out image formation on command. At the same time, image formation cannot be carried out during physical formatting or data clearing of the HDD. However, the heat rollers of the heat fixing device are nonetheless maintained in a high-heat state during this period, resulting in the consumption of a large amount of power.
The image forming apparatuses disclosed in Japanese Patent Application Laid-Open No. 2001-277603 or Japanese Patent Application Laid-Open No. 2001-285600 above have an object of reducing the time required to reach operability when the power to the apparatus is turned ON, and do not involve reducing the power consumption of the entire image forming apparatus during physical formatting or data clearing of the HDD.